1. Field of the Invention
The present invention relates to an information display system provided with a touch panel suitable for a navigation system or the like.
2. Related Art
In prior art information display systems having touch panels, a variety of information such as menu items are displayed on a display unit, and choices are input by manually touching selected items of the displayed information through the touch panel. When a manual touch is detected, the touch position coordinates on the screen are detected to determine which of the items displayed on the screen has been selected, and processing proceeds in accordance with the item which was selected.
In one vehicular navigation system of the prior art, the display unit is provided with a touch panel to make it easier for an operator to make a variety of settings and to present the information while the vehicle is running. If an item of a particular type such as a convenience store, a gas station or a fast food restaurant is selected on the screen of the navigation system, a landmark of the selected type is displayed on the map in the screen so that the user can easily recognize at a glance the location of the shop of the selected type.
In the aforementioned navigation system of the prior art, a displayed landmark can be selected by touching the desired landmark on the display screen to set a transition point or a destination point for the navigation system. However if the displayed map covers an urbane district or a wide area, a plurality of the landmarks may be densely displayed on the display screen.
The method of selecting a displayed landmark by the touch screen is advantageous in that the landmark can be selected by a single touch. However, the item selected by manual touch may be ambiguous (incapable of being determined) if the landmark to be selected is one of a plurality of closely spaced landmarks.
Thus an erroneous selection can result when densely displayed landmarks are selected through the touch panel, as described above. Even when the user recognizes the erroneous selection and repeats the input, the erroneous selection can be repeated if the dense display state is unchanged. Where items to be selected by touch are displayed densely on the display, erroneous selections occur frequently.